Clinical Question

Does self-monitoring or self-management improve the safety, effectiveness, and feasibility of long-term oral anticoagulation therapy compared with traditional monitoring?

Evidence-Based Answer

In patients taking warfarin (Coumadin) for anticoagulation, there is moderate-quality evidence that both self-monitoring (number needed to treat [NNT] = 100) and self-management (NNT = 53) reduce thromboembolic events, and that self-management reduces all-cause mortality (NNT = 67). There is low- to moderate-quality evidence that neither self-management nor self-monitoring reduces major or minor hemorrhage. Physicians should consider self-management or self-monitoring for patients who are willing and able to use these strategies.1 (Strength of Recommendation: A, based on consistent, good-quality patient-oriented evidence.)

Practice Pointers

Portable point-of-care (POC) devices for monitoring long-term oral anticoagulation have been available since the 1990s. Self-monitoring is a strategy in which the patient can measure his or her international normalized ratio (INR) with a POC device, then adjust warfarin dosing by calling a clinic for advice. Self-management strategies refer to patient use of a POC device to measure the INR and adjust warfarin dosage according to a predetermined schedule on physician-approved algorithms. Advantages of both strategies may include patient convenience, ease of monitoring, and fewer thromboembolic complications. A 2006 study suggested that self-monitoring and self-management are cost-effective strategies for those receiving long-term oral anticoagulation.2

A previous version of this review found that use of POC devices by patients for self-monitoring or self-management of anticoagulation improved all-cause mortality, rates of venous thromboembolism, and rates of minor hemorrhage. Self-monitoring also improved rates of major hemorrhage.3

In updating this Cochrane review, the authors found 10 new trials with 4,227 additional patients to bring the aggregate to 28 randomized controlled trials including 8,950 participants.1 The authors assessed risk of bias as low to moderate because blinding participants to allocation was not possible. Studies lasted from three months to nearly five years.